A systematic review and meta-analysis of the use of methylene blue to improve the lymph node harvest in rectal cancer surgery.

BACKGROUND: Methylene blue staining of the resected specimen has been described as an alternative to the conventional palpation and visual inspection method to improve lymph node harvest. This meta-analysis evaluates the usefulness of this technique in surgery for rectal cancer, particularly after neoadjuvant therapy. METHODS: Randomized controlled trials (RCTs) comparing lymph node harvest in methylene blue-stained rectal specimens to those of unstained specimens were identified from the Medline, Embase, and Cochrane databases. Non-randomized studies and those with only colonic resections were excluded. The quality of RCTs was assessed using Cochrane's risk of bias tool. A weighted mean difference (WMD) was calculated for overall harvest, harvest after neoadjuvant therapy, and metastatic nodal yield. In contrast, the risk difference (RD) was calculated to compare yields of less than 12 lymph nodes between the stained and unstained specimens. RESULTS: Study selection comprised seven RCTs with 343 patients in the unstained group and 337 in the stained group. Overall lymph node harvest and harvest after neoadjuvant therapy were significantly higher in stained specimens with a WMD of 13.4 and 10.6 and a 95% confidence interval (CI) of 9.5-17.2 and 4.8-16.3, respectively. Harvest of metastatic lymph nodes was significantly higher in the stained group (WMD 1.0, 95% CI 0.6-1.4). The yield of less than 12 lymph nodes was significantly higher in the unstained group with RD of 0.292 and 95% CI of 0.182-0.403. CONCLUSION: Despite a small number of patients, this meta-analysis confirms improved lymph node harvest in surgical specimens stained with methylene blue compared with unstained specimens.

Development of mesenteric tissues.

Mesothelial, neurovascular, lymphatic, adipose and mesenchymal tissues make up the mesentery. These tissues are pathobiologically important for numerous reasons. Collectively, they form a continuous, discrete and substantive organ. Additionally, they maintain abdominal digestive organs in position and in continuity with other systems. Furthermore, as they occupy a central position, they mediate transmission of signals between the abdominal digestive system and the remainder of the body. Despite this physiologic centrality, mesenteric tissue development has received little investigatory focus. However, recent advances in our understanding of anatomy demonstrate continuity between all mesenteric tissues, thereby linking previously unrelated studies. In this review, we examine the development of mesenteric tissue in normality and in the setting of congenital abnormalities.

Anatomy of the mesentery: Historical development and recent advances.

Recent appraisals of mesenteric anatomy clarify its structure and show a continuous and helical-shaped organ. This new model signifies a departure from the conventional model which described multiple, separate "mesenteries". Renaissance anatomists depicted the mesentery as a continuous structure. Events that led to replacement of a continuous with a fragmented model span several centuries. In effect, the scientific and clinical community has come full circle and back to the Renaissance model. Here we review the historical development of our understanding of the mesentery. We discuss how the fragmented model replaced the continuous model. Additionally, we examine factors that contributed to recent advances in mesenteric anatomy as these present new opportunities for systematic investigation.

Anatomy of the mesentery: Current understanding and mechanisms of attachment.

An understanding of the anatomy of the mesentery is necessary to undertake any appraisal of the literature on its development. The mesentery is the collection of tissues that maintain all abdominal digestive organs in position and connection with the rest of the body. Therefore, it is also necessary to detail the exact mechanisms that maintain the mesentery in position. We explore these mechanisms, including the supportive functions of structures such as Toldt's fascia, the peritoneal reflection, and vascular connections, in this article.

A meta-analysis of low Hartmann's procedure versus abdominoperineal resection for non-restorative treatment of rectal cancer.

BACKGROUND: Non-restorative surgery for rectal cancer is indicated in patients with comorbidities, advanced disease and poor continence. The aim of this meta-analysis was to compare the postoperative morbidity of Hartmann's procedure (HP) with that of extrasphincteric and intersphincteric abdominoperineal resection (APR) in the treatment of rectal cancer. METHODS: The Medline, Embase and Cochrane databases were searched for publications comparing postoperative morbidity of HP and APR. The incidence of overall surgical complications, pelvic-perineal complications and pelvic abscess was analysed as primary endpoints. Readmissions requiring reintervention and postoperative mortality were also compared. RESULTS: A cumulative analysis showed a significantly higher rate of overall complications (odds ratio (OR) 0.553, 95% confidence interval (CI) 0.320 to 0.953 and P value 0.033) and pelvic-perineal complications (OR 0.464, 95% CI 0.250 to 0.861 and P value 0.015) after APR. The incidence of isolated pelvic abscess formation was significantly higher after HP (OR 2.523, 95% CI 1.383 to 4.602 and P value 0.003). A subgroup analysis of intersphincteric APR compared with HP did not show any significant difference in the incidence of overall complications, pelvic-perineal complications or pelvic abscess formation (P values of 0.452, 0.258 and 0.100, respectively). There was no significant difference in readmissions, reinterventions and mortality after HP and APR (P 0.992, 0.198 and 0.151). CONCLUSION: An extrasphincteric APR is associated with higher overall and pelvic-perineal complications and may be reserved for tumours invading the anal sphincter complex. In the absence of sphincter involvement, both HP and intersphincteric APR are better alternatives with comparable morbidity.

Communication, collaboration and contagion: "Virtualisation" of anatomy during COVID-19.

COVID-19 has generated a global need for technologies that enable communication, collaboration, education and scientific discourse whilst maintaining physical distance. University closures due to COVID-19 and physical distancing measures disrupt academic activities that previously occurred face-to-face. Restrictions placed on universities due to COVID-19 have precluded most conventional forms of education, assessment, research and scientific discourse. Anatomists now require valid, robust and easy-to-use communication tools to facilitate remote teaching, learning and research. Recent advances in communication, video conferencing and digital technologies may facilitate continuity of teaching and research activities. Examples include highly-interactive video conferencing technology, collaborative tools, social media and networking platforms. In this narrative review, we examine the utility of these technologies in supporting effective communication and professional activities of anatomists during COVID-19 and after.

Prophylactic Negative Pressure Dressing Use in Closed Laparotomy Wounds Following Abdominal Operations: A Randomized, Controlled, Open-label Trial: The P.I.C.O. Trial.

OBJECTIVE: A randomized controlled trial was undertaken to investigate the effect of prophylactic negative pressure dressings on postoperative surgical site infection (SSI) rates in closed laparotomy wounds. SUMMARY OF BACKGROUND DATA: Laparotomy wounds are associated with high rates of SSI. The effect of prophylactic negative pressure dressing of closed incisional wounds on SSI rate is unknown. METHODS: A randomized, controlled, open-label trial was conducted (clinicaltrials.gov registration number NCT02780453). Fifty patients undergoing open abdominal surgery were included, with 25 patients randomized to the negative pressure dressing group and 25 to the standard dressing group. The primary endpoint was SSI incidence at 30 days postoperatively. Secondary endpoints included SSI incidence at 4 days, length of stay, cosmetic outcome, and patient satisfaction. Statistical analysis was performed on a per-protocol basis using SPSS version 23.0. RESULTS: The incidence of SSI at 30 days postoperatively was significantly reduced in the treatment group compared with the control group [8.3% vs 32.0%, P = 0.043 (1-sided), P = 0.074 (2-sided)]. There was no difference in SSIs at 4 days postoperatively [4.1% vs 8.0%, P = 0.516 (1-sided), P = 1.0 (2-sided)]. Analysis of predictors of wound infection identified standard wound dressings as the only significant predictor of SSI development. Length of stay was significantly reduced in the negative pressure dressing group [6.1 vs 14.7 days, P = 0.019 (2-sided)]. Cosmetic outcome and patient satisfaction did not show any difference between the 2 groups. CONCLUSIONS: Prophylactic use of negative pressure dressings for closed laparotomy wounds significantly reduces the incidence of SSI at 30 days postoperatively.

The mesentery in Crohn's disease: friend or foe?

PURPOSE OF REVIEW: This article assesses the role of the mesentery in Crohn's disease. RECENT FINDINGS: The mesentery is centrally positioned both anatomically and physiologically. Overlapping mesenteric and submucosal mesenchymal contributions are important in the pathobiology of Crohn's disease. Mesenteric contributions explain the topographic distribution of Crohn's disease in general and mucosal disease in particular. Operative strategies that are mesenteric based (i.e. mesocolic excision) may reduce rates of postoperative recurrence. SUMMARY: The net effect of mesenteric events in Crohn's disease is pathologic. This can be targeted by operative means. VIDEO ABSTRACT: http://links.lww.com/COG/A18.

Lymphovascular invasion: a comprehensive appraisal in colon and rectal adenocarcinoma.

BACKGROUND: Colon and rectal adenocarcinomas differ at a multitude of levels. The association between outcome and predictor in 1 group may obscure the relationship between outcome and predictor in the other. OBJECTIVE: The current study aims to evaluate the prognostic properties of lymphovascular invasion in colon and rectal adenocarcinoma separately. MATERIALS AND METHODS (DESIGN, SETTING AND PATIENTS): A comparative retrospective analysis was undertaken to determine the prognostic properties of lymphovascular invasion in colon and rectal adenocarcinomas. Patients were classified as lymphovascular invasion positive and lymphovascular invasion negative in separate colon and rectal cancer cohorts. Within cohorts, a univariate analysis was undertaken to determine the association between lymphovascular invasion positivity and local/systemic recurrence and overall/disease-free survival. Findings were evaluated by using Kaplan-Meier estimates, log-rank analysis, and a Cox proportional hazards multivariate model. MAIN OUTCOME MEASURE: The primary outcomes measured were overall and disease-free survival. RESULTS: Five hundred twenty-seven patients were included in the analysis (379 with colon cancer and 148 with rectal cancer). On univariate analysis, lymphovascular invasion positivity was associated with adverse locoregional recurrence in colon (p = 0.002) but not rectal adenocarcinoma (p = 0.13). Conversely, lymphovascular invasion positivity was associated with adverse systemic recurrence in rectal (p = 0.002) but not colon adenocarcinoma (p = 0.35). On multivariate analysis, lymphovascular invasion positivity was an independent predictor of adverse disease-free survival in colon (p = 0.02) and rectal adenocarcinoma (p < 0.001). Regarding overall survival, lymphovascular invasion positivity was a poor prognostic indicator in rectal adenocarcinoma only (p = 0.04). LIMITATIONS AND CONCLUSIONS: In this retrospective analysis, lymphovascular invasion positivity was associated with different patterns of disease recurrence in colon and rectal cancer. Lymphovascular invasion positivity was associated with adverse overall survival in rectal cancer only.

Preoperative staging CT thorax in patients with colorectal cancer: its clinical importance.

BACKGROUND: Recent studies suggest that there is little benefit to routine preoperative staging CT of the thorax in colorectal cancer. OBJECTIVE: The current study hypothesized that staging CT of the thorax is not mandated in all patients with colorectal cancer. DESIGN: This study was a tertiary-care center retrospective observational study. PATIENTS: Patients with a diagnosis of colon and rectal adenocarcinoma during 2006 to 2011 were included in a hospital database. Demographic, pathological, radiological, survival, and clinical factors were recorded. Three hundred eighty-two patients were included in the analysis (234 male, 148 female). INTERVENTIONS: All patients underwent preoperative staging CT of the thorax to determine the presence of pulmonary metastasis and/or indeterminate lesions. MAIN OUTCOME MEASURES: Patients demographics were reviewed, and the factors associated with pulmonary metastasis and indeterminate lesions were evaluated. RESULTS: Distant metastases were evident in 61 patients (16%). CT scans revealed pulmonary metastasis in 23 patients (6%), and indeterminate lesions in 33 (8.6%). Only one-third of pulmonary lesions were evident on chest x-ray. On logistic regression analysis, nodal positivity was associated with an increased risk for pulmonary metastasis (p = 0.03). There was no difference in overall survival between patients with pulmonary metastasis and indeterminate lesions (p = 0.35, Kaplan-Meier estimate, log rank analysis). Pulmonary metastasis developed during postoperative surveillance in 7 patients with indeterminate lesions (21.2%). LIMITATIONS: This is a retrospective, single-center study with a relatively small sample size. CONCLUSIONS: Pulmonary metastasis is relatively rare in colorectal cancer, and staging CT of the thorax may not be mandated in low-risk patients.

Ileal pouch anal anastomosis: analysis of outcome and quality of life in 3707 patients.

BACKGROUND: Ileal pouch anal anastomosis (IPAA) is the treatment of choice for chronic, medically refractory mucosal ulcerative colitis, indeterminate colitis, familial adenomatous polyposis (FAP), and a select group of patients with Crohn's disease. AIM: : We report outcomes, complications, and quality of life (QOL) in a cohort of 3707 patients treated at our institution from January 1984 to March 2010. METHODS: Data were collected from a prospectively maintained database and chart review of 3707 consecutive primary IPAA cases. Patient demographics, postoperative complications, functional outcomes, and QOL data were available. Follow-up consisted of clinical examination with assessment of pouch function and QOL. RESULTS: A total of 3707 patients underwent primary pouch and 328 underwent redo pouch surgery. Postoperative histopathological diagnoses were mucosal ulcerative colitis (n = 2953, 79.7%), indeterminate colitis (n = 63, 1.7%), FAP (n = 223, 6%), Crohn's disease (n = 150, 4%), cancer/dysplasia (n = 97, 2.6%), and others (n = 221, 6.0%). Early perioperative complications were encountered in 33.5% of patients with a mortality rate of 0.1%. Excluding pouchitis, late complications were experienced by 29.1% of patients. Of those patients who had IPAA at our institution, pouch failure occurred in 197 patients (5.3%). During a median follow-up of 84 months, 119 patients (3.2%) required excision of the pouch, 32 (0.8%) had a nonfunctioning pouch, and 46 patients (1.2%) had redo IPAA. Functional outcomes and QOL were good or excellent in 95% of patients and similar in each histopathological subgroup. CONCLUSIONS: IPAA is an excellent option for patients with MUC, IC, FAP, and select patients with Crohn's disease.

Robotic colorectal surgery in elderly patients: A single-centre experience.

INTRODUCTION: The purpose of this study was to evaluate outcomes in elderly patients (age ≥ 65 years) undergoing robotic colorectal surgery (RCRS) in comparison with non-elderly patients. MATERIALS AND METHODS: Data was collected on elderly and non-elderly patients who underwent RCRS from a prospectively maintained database. RESULTS: A total of 89 elderly and 73 non-elderly patients were identified. No statistically significant differences in postoperative complication, reoperation, wound infection, anastomotic leak or mortality were observed. The median length of stay was 1 day longer in elderly patients (p = 0.007). Subgroup analysis of octogenarians demonstrated outcomes that compared favourably with younger patients. CONCLUSION: RCRS in elderly patients is safe and effective, with outcomes that do not differ significantly with younger patients. Older age should not be considered to be a specific exclusion criteria for RCRS. To our knowledge, this study represents the largest in the literature to examine outcomes specifically in elderly patients undergoing RCRS.

The first robotic transanal minimally invasive surgery in Ireland: a case-based review.

Transanal minimally invasive surgery (TAMIS) has gained worldwide acceptance as a means of local excision of early rectal cancers and benign rectal lesions. However, it is technically challenging due to the limitations of rigid laparoscopic instruments in the narrow rectal lumen. Robotic platforms offer improved ergonomics that are valuable in operative fields with limited space. Robotic TAMIS represents an exciting new development that may be more versatile than traditional TAMIS. In this review, we describe the first case of robotic TAMIS performed in our country and a review of current literature on the technique.

Necrotising fasciitis in the COVID-19 era: A consequence of caution - A case series.

Necrotising fasciitis (NF) is a severe soft tissue infection that is associated with a high risk of morbidity and mortality. During the coronavirus disease 19 (COVID-19) pandemic, the population has been actively discouraged from presenting to emergency medical services unless absolutely necessary. While this was an important step in allowing for preservation of limited resources in a time of crisis, it may have resulted in immeasurable 'secondary victims' of the pandemic as patients with time-critical conditions delay hospital presentation. In this case series, we describe three patients that noted symptoms of soft tissue infection, but delayed seeking healthcare advice due to concerns regarding COVID-19 exposure. All three progressed to NF, requiring highly morbid wide surgical debridement and prolonged hospital admission, with a high risk of potential mortality. The findings of this series demonstrate the importance of consistently delivering appropriate and timely healthcare interventions to patients with non-COVID-19-related conditions. While efforts must be made to ensure preservation of valuable healthcare resources in a global pandemic, patients must also be empowered to seek timely care for non-COVID-19-related conditions even in this time of crisis.

The impact of body mass index on outcomes in robotic colorectal surgery: a single-centre experience.

Obesity is an independent risk factor for postoperative morbidity and mortality in laparoscopic colorectal surgery (LCRS). The technological advantages of robotic colorectal surgery (RCRS) may allow surgeons to overcome the limitations of LCRS in obese patients, but it is largely unknown if this translates to superior outcomes. The aim of this study was to compare perioperative, postoperative and short-term oncological outcomes in obese (BMI ≥ 30.0 kg/m2) and non-obese (BMI < 30 kg/m2) patients undergoing RCRS in a university teaching hospital. Demographic, perioperative and postoperative data along with short-term oncological outcomes of obese and non-obese patients that underwent RCRS for both benign and malignant colorectal disease were identified from a prospectively maintained database. A total of 107 patients (34 obese, 73 non-obese) underwent RCRS over a 4-year period. No statistically significant differences in the incidence of complications, 30-day reoperation, 30-day mortality, conversion to open surgery, anastomotic leak or length of inpatient stay were demonstrated. Obese patients had a significantly higher rate of surgical site infection (SSI) (p < 0.0001). Short-term oncological outcomes in both groups were favourable. There was no statistically significant difference in median duration of surgery between the two cohorts. The results demonstrate that obese patients undergoing RCRS in this institution experience similar outcomes to non-obese patients. These results suggest that RCRS is safe and feasible in obese patients and may be superior to LCRS in this cohort, where the literature suggests a higher complication rate compared to non-obese patients. The inherent advantages of robotic surgical platforms, such as improved visualisation, dexterity and ergonomics likely contribute to the improved outcomes in this challenging patient population.

Robotic versus laparoscopic right hemicolectomy: a case-matched study.

The current gold standard surgical treatment for right colonic malignancy is the laparoscopic right hemicolectomy (LRH). However, laparoscopic surgery has limitations which can be overcome by robotic surgery. The benefits of robotics for rectal cancer are widely accepted but its use for right hemicolectomy remains controversial. The aim of this study was to compare outcomes in patients undergoing robotic right hemicolectomy (RRH) and LRH in a university teaching hospital. Demographic, perioperative and postoperative data along with early oncological outcomes of patients who underwent RRH and LRH with extracorporeal anastomosis (ECA) were identified from a prospectively maintained database. A total of 70 patients (35 RRH, 35 LRH) were identified over a 4-year period. No statistically significant differences in estimated blood loss, conversion to open surgery, postoperative complications, anastomotic leak, 30-day reoperation, 30-day mortality, surgical site infection or lengths of stay were demonstrated. Surgical specimen quality in both groups was favourable. The mean duration of surgery was longer in RRH (p < < 0.00001). A statistically significant proportion of RRH patients had a higher BMI and ASA grade. The results demonstrate that RRH is safe and feasible when compared to LRH, with no statistical difference in postoperative morbidity, mortality and early oncological outcomes. A difference was noted in operating time, however was influenced by training residents in docking the robot and a technically challenging cohort of patients. Operative time has shortened with further experience. Incorporating an intracorporeal anastomosis technique in RRH offers the potential to improve outcomes compared to LRH.

A characterization of factors determining postoperative ileus after laparoscopic colectomy enables the generation of a novel predictive score.

BACKGROUND/OBJECTIVE: Postoperative ileus (POI) after colorectal surgery is associated with prolonged hospital stay and increased costs. The aim of this study is to investigate pre-, intra-, and postoperative risk factors associated with the development of POI in patients undergoing laparoscopic partial colectomy. METHODS: Patients operated between 2004 and 2008 were retrospectively identified from a prospectively maintained database, and clinical, metabolic, and pharmacologic data were obtained. Postoperative ileus was defined as the absence of bowel function for 5 or more days or the need for reinsertion of a nasogastric tube after starting oral diet in the absence of mechanical obstruction. Associations between likelihood of POI and study variables were assessed univariably by using χ tests, Fisher exact tests, and logistic regression models. A scoring system for prediction of POI was constructed by using a multivariable logistic regression model based on forward stepwise selection of preoperative factors. RESULTS: A total of 413 patients (mean age, 58 years; 53.5% women) were included, and 42 (10.2%) of them developed POI. Preoperative albumin, postoperative deep-vein thrombosis, and electrolyte levels were associated with POI. Age, previous abdominal surgery, and chronic preoperative use of narcotics were independently correlated with POI on multivariate analysis, which allowed the creation of a predictive score. Patients with a score of 2 or higher had an 18.3% risk of POI (P < 0.001). CONCLUSION: Postoperative ileus after laparoscopic partial colectomy is associated with specific preoperative and postoperative factors. The likelihood of POI can be predicted by using a preoperative scoring system. Addressing the postoperative factors may be expected to reduce the incidence of this common complication in high-risk patients.